The present invention relates to arithmetic instruction apparatuses and, in particular, relates to a teaching aid for assisting an instructor in teaching arithmetic functions to children.
Quite commonly when a child begins to learn arithmetic, counting is illustrated with the use of the fingers. The child is told he has ten fingers, and once he has learned to count to ten, he will use his fingers to count and to illustrate numbers. Even later on in life the fingers are commonly used for counting. For example, baseball umpires indicate the number of balls and strikes with their fingers, and public speakers often indicate the number of points they will make by holding up a corresponding number of fingers. The decimal system was very likely based on the number 10 because of the ten fingers.
Through the years a variety of mechanical devices and systems have been used to facilitate counting and arithmetic operations. The abacus is one of the oldest and most widely known mechanical devices. For example of various mechanical devices used for teaching and accomplishing certain arithmetic operations, see for example, U.S. Pat. Nos. 3,731,401; 3,508,348; 3,455,034; 3,092,917; 2,888,753; D 9303; D 181,754; D 203,176; and D 215,004.
However, the mechanical devices of the prior art are generally rectangular in outline and bear no relationship to the hands of the user. Thus a certain amount of abstract thinking is required which is sometimes a serious problem for certain youngsters learning to perform basic arithmetic operations.
There is therefore a need for a mechanical teaching device which can be mastered by the young student at a early stage in learning basic arithmetic functions.